Quote:
| Originally Posted by NotDeadYet Hi John,
each to their own. For me the psychological benefit of switching to a system in an emergency that I know will work and will be safe to breathe instantly outweighs what anyone thinks of my completeness. I'd rather be an alive shit diver than a dead good one. If the loop can be salvaged all well and good but my first stop is my OC reg.
A hell of a lot more than a torn loop hose will flood a RB: punctured counterlung, failed o-ring, punctured ADV diaphragm, torn cable sheath (if using ambient pressure handsets), warped scrubber (happens on Draegers)... I guess one of the benefits of homebuilding is the risk analysis and failure mode studies that you go through.
Cheers,
Stuart |
I fully agree Stuart. Get to breathable (known safe) gas asap then assess the situation with the ultimate aim if possible to go back to the loop.
However I do it a slightly different way because in the case of a CO2 hit In practice its often
not possible to bail off a RB to OC
For 'dodgy gas problems' I practice the faster and more easily accomplished 'if in doubt fire the ADV method'
I had a CO2 hit once where I ended up laying on the sea bed fully aware that I was having a CO2 hit but my arms just wouldn't move. I knew I should bail but it seamed like just too much trouble and the thought of leaving the perceived comfort and safety of the loop was just not an option. I knew all I had to do was grab my reg. I knew I had plenty of OC gas (believe it or not I was only at 25m!!) I remember thinking I should bail to OC but just couldn't be bothered to move my arms at all. Then I thought maybe a flush would be good - but still I just was feeling very incapacitated and just didn't want to be bothered with moving at all. I was laying flat out on the sand with my arms by my side like an idiot just breathing not moving and getting more and more useless by the second. Some how and for some reason I started breathing out every breath thru my nose thus firing the ADV and thus flushing the loop. After a few minutes of this I began to feel better and I sorted myself out. I went back to the loop semiclosed and turned the dive.
I think looking back in my lethargic state any excess movement (flushing, bailing) was just abhorrent to me as was the thought of leaving the perceived safety of the loop. By firing the ADV I didn't have or do either and I think it saved me. Now my first action if I get a CO2 hit is not to bail as I think from what Ive read its not always mentally possible - my first reaction is to breathe out thru my nose and fire the ADV on each breath. It only takes one or two breaths to be on effectively OC anyway.
I personally believe this should be taught in training rather than the bail to OC mantra - as we know that doesn't work.
Once the fresh gas has cleared the head then asap I can bail properly to OC or stay on the loop and manage the situation.
Since this happened a few years ago I am now using a OC/CC switching mouthpiece - but recently I heard a story from one diver who said he was even unable to switch his OC/CC valve when he had an CO2 hit.
People and training agencies that glibly assume its easy to bail off a RB to OC in the case of an CO2 hit are dangerously fooling themselves - there should be better awareness that if the CO2 gets you your probably going to be a pile of useless sh1t and not able to do anything to save yourself - not even to swap a reg.
So my mantra is
if you are starting to doubt - fire the ADV (breathe out thru the nose)
if in doubt (and if able to) bail out to OC
- then
if deep enough or in overhead where gas vol could be an issue try to see if you can go back to the loop' (If your in 15m of water and no deco why risk going back to a loop that could be compromised?)
Cheers
Mike